Michael, here are the regs for SS engines from 2004 Classic Adelaide. I don't want to be a wet blanket but I can't see anything in here that would allow boat tailing or knife edging. Given the aggro caused to a number of Porsche guys in the past, I'd strongly reccommend getting a ruling to remain above reproach. Also, 10.3:1 ??? C/R.
QUOTE...
The original engine specification as supplied by the vehicle manufacturer for the make and model
concerned, must be employed. Mechanical modifications are forbidden except for the following:
(i) overboring is only permitted within the manufacturers normal specified reconditioning
tolerances (this is generally restricted to around 0.5mm increase in diameter).
(ii) pistons are free, however they must be dimensionally the same as original, except for the
diameter, which is only allowed to be varied as per (i) above.
(iii) reconditioning of other engine components within the manufacturers' specified tolerances
is permitted.
(iv) the original head may be modified by the removal of metal only. The valve sizes must
remain standard. The compression ratio must remain as standard.
(v) camshaft timing and lif t is free.
(vi) for rotary engines, the only allowable modification is "extended porting". In addition, the
exhaust port inserts must remain standard and in their normal place. "Bridgeporting" or
"peripheral porting" is not permitted.
(vii) the original ignition system must be retained save that 'pointless' distribution operation
may be substituted for breaker points. Freedom of mechanical and vacuum advance
mechanisms is allowed, as is freedom of ignition wires, spark plugs, etc.
(viii) turbochargers or superchargers, if fitted as original equipment, must remain standard, as
must the method of controlling boost or pressure. The amount of boost or pressure must
be standard as specified by the manufacturer.
(ix) the complete original induction system must be retained, without additions or deletions.
The components which control the quantity of fuel entering the combustion chamber may
be modified, provided that they do not have any influence over the quantity of air
admitted. Replacement air filter cartridges are permitted as long as they fit into the
original air cleaner(s). Additional air ducting is not permitted. Fuel pumps are free.
(x) the exhaust system is free past the point of entry into the first muffler. The exhaust pipe
must exit at the original point on the vehicle.
(xi) engine liquid cooling systems (ie water and oil) must remain as standard, although the
radiator may be replaced by one of the same size, but of greater thickness. The original
cooling fan(s) must be retained unaltered, but one additional electric fan may be added.
Thermostats may be removed.
(xii) air cooled engines must retain the standard system, although the speed ratio may be
changed.
(xiii) ancillary items such as starters, generators, etc., may be uprated, provided that the
original type is respected.
(xiv) clutches may be uprated only by the changing of springs, diaphragms or linings, however
the remainder of the clutch assembly must be original.
(xv) engine sumps may have internal baffling but the sump shape and capacity must be
standard.
END QUOTE...
Thats it........
